NFPA 921 (CHAPTER 5) Exam 2025
Questions and Answers
What is energy? - ANSWER✔✔-Ability to perform work, either by moving over a distance against
a force or by transferring heat.
How is energy measured - ANSWER✔✔-Joules, calories, or BTU's
Define power - ANSWER✔✔-Property that describes energy released per unit time.
How is power measured? - ANSWER✔✔-Joules per second or watts.
Define heat flux - ANSWER✔✔-The amount of power per unit area.
What are the 4 components of the Fire Tetrahedron - ANSWER✔✔-1. Fuel 2. Heat 3. Oxidizing
agent 4. Chemical chain reaction.
What is fuel - ANSWER✔✔-Any substance that can undergo combustion.
What is the Oxidizing agent - ANSWER✔✔-Oxygen in the earths's atmosphere
What is fire chemistry - ANSWER✔✔-Study of chemical processes that occur in fires, including
changes of state, decomposition, and combustion.
define combustion - ANSWER✔✔-Fuel and Oxidizing agent mixed (premixed burning)
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 1
Questions and Answers
What is energy? - ANSWER✔✔-Ability to perform work, either by moving over a distance against
a force or by transferring heat.
How is energy measured - ANSWER✔✔-Joules, calories, or BTU's
Define power - ANSWER✔✔-Property that describes energy released per unit time.
How is power measured? - ANSWER✔✔-Joules per second or watts.
Define heat flux - ANSWER✔✔-The amount of power per unit area.
What are the 4 components of the Fire Tetrahedron - ANSWER✔✔-1. Fuel 2. Heat 3. Oxidizing
agent 4. Chemical chain reaction.
What is fuel - ANSWER✔✔-Any substance that can undergo combustion.
What is the Oxidizing agent - ANSWER✔✔-Oxygen in the earths's atmosphere
What is fire chemistry - ANSWER✔✔-Study of chemical processes that occur in fires, including
changes of state, decomposition, and combustion.
define combustion - ANSWER✔✔-Fuel and Oxidizing agent mixed (premixed burning)
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 1
